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Hydrogeologic data from a shallow flooding demonstration project, Twitchell Island, California, 1997-2001

James M. Gamble·Karen R. Burow·Gail A. Wheeler·Robert Hilditch·Judy Z. Drexler
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Abstract

Data were collected during a study to determine the effects of continuous shallow flooding on ground-water discharge to an agricultural drainage ditch on Twitchell Island, California. The conceptual model of the hydrogeologic setting was detailed with soil coring and borehole-geophysical logs. Twenty-two monitoring wells were installed to observe hydraulic head. Ten aquifer slug tests were done in peat and mineral sediments. Ground-water and surface-water temperature was monitored at 14 locations. Flow to and from the pond was monitored through direct measurement of flows and through the calculation of a water budget. These data were gathered to support the development of a two-dimensional ground-water flow model. The model will be used to estimate subsurface discharge to the drainage ditch as a result of the pond. The estimated discharge will be used to estimate the concentrations of DOC that can be expected in the ditch.

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James M. Gamble, Karen R. Burow, Gail A. Wheeler, Robert Hilditch, Judy Z. Drexler. 2003. Hydrogeologic data from a shallow flooding demonstration project, Twitchell Island, California, 1997-2001. https://doi.org/10.3133/ofr03378

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